Validity of suspected alcohol and drug violations in aviation employees

Random drug and alcohol testing for preventing injury in workers

BACKGROUND

Drug- and alcohol-related impairment in the workplace has been linked to an increased risk of injury for workers. Randomly testing populations of workers for these substances has become a practice in many jurisdictions, with the intention of reducing the risk of workplace incidents and accidents. Despite the proliferation of random drug and alcohol testing (RDAT), there is currently a lack of consensus about whether it is effective at preventing workplace injury, or improving other non-injury accident outcomes in the work place.

OBJECTIVES

To assess the effectiveness of workplace RDAT to prevent injuries and improve non-injury accident outcomes (unplanned events that result in damage or loss of property) in workers compared with no workplace RDAT.

SEARCH METHODS

We conducted a systematic literature search to identify eligible published and unpublished studies. The date of the last search was 1 November 2020. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, two other databases, Google Scholar, and three trials registers. We also screened the reference lists of relevant publications known to us.

SELECTION CRITERIA

Study designs that were eligible for inclusion in our review included randomised controlled trials (RCTs), cluster-randomised trials (CRTs), interrupted time-series (ITS) studies, and controlled before-after (CBA) studies. Studies needed to evaluate the effectiveness of RDAT in preventing workplace injury or improving other non-injury workplace outcomes. We also considered unpublished data from clinical trial registries. We included employees working in all safety-sensitive occupations, except for commercial drivers, who are the subject of another Cochrane Review.

DATA COLLECTION AND ANALYSIS

Independently, two review authors used a data collection form to extract relevant characteristics from the included study. They then analysed a line graph included in the study of the prevalence rate of alcohol violations per year. Independently, the review authors completed a GRADE assessment, as a means of rating the quality of the evidence.

MAIN RESULTS

Although our searching originally identified 4198 unique hits, only one study was eligible for inclusion in this review. This was an ITS study that measured the effect of random alcohol testing (RAT) on the test positivity rate of employees of major airlines in the USA from 1995 to 2002. The study included data from 511,745 random alcohol tests, and reported no information about testing for other substances. The rate of positive results was the only outcome of interest reported by the study. The average rate of positive results found by RAT increased from 0.07% to 0.11% when the minimum percentage of workers who underwent RAT annually was reduced from 25% to 10%. Our analyses found this change to be a statistically significant increase (estimated change in level, where the level reflects the average percentage points of positive tests = 0.040, 95% confidence interval 0.005 to 0.075; P = 0.031). Our GRADE assessment, for the observed effect of lower minimum testing percentages associating with a higher rate of positive test results, found the quality of the evidence to be 'very low' across the five GRADE domains. The one included study did not address the following outcomes of interest: fatal injuries; non-fatal injuries; non-injury accidents; absenteeism; and adverse effects associated with RDAT.

AUTHORS' CONCLUSIONS

In the aviation industry in the USA, the only setting for which the eligible study reported data, there was a statistically significant increase in the rate of positive RAT results following a reduction in the percentage of workers tested, which we deem to be clinically relevant. This result suggests an inverse relationship between the proportion of positive test results and the rate of testing, which is consistent with a deterrent effect for testing. No data were reported on adverse effects related to RDAT. We could not draw definitive conclusions regarding the effectiveness of RDAT for employees in safety-sensitive occupations (not including commercial driving), or with safety-sensitive job functions. We identified only one eligible study that reflected one industry in one country, was of non-randomised design, and tested only for alcohol, not for drugs or other substances. Our GRADE assessment resulted in a 'very low' rating for the quality of the evidence on the only outcome reported. The paucity of eligible research was a major limitation in our review, and additional studies evaluating the effect of RDAT on safety outcomes are needed.

Reducing the Incidence of Substance Use Disorders in Anesthesiology Residents: 13 Years of Comprehensive Urine Drug Screening

WHAT WE ALREADY KNOW ABOUT THIS TOPIC

WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: The incidence of substance use disorders in the United States among residents in anesthesiology is between 1% and 2%. A recent study reported that the incidence of substance use disorders in U.S. anesthesiology residents has been increasing. There are no reports of effective methods to prevent substance use disorder in residents. A comprehensive drug testing program including a random component may reduce the incidence of substance use disorders.

METHODS

The authors initiated a comprehensive urine drug screening program of residents, fellows, faculty physicians, and certified nurse anesthetists. The authors performed 3,190 tests over 13 yr. The authors determined the incidence of substance use disorders among residents in our large anesthesiology residency program during the decade before (January 1, 1994, to December 31, 2003) and for the 13 yr after (January 1, 2004 to December 31, 2016) instituting a random urine drug testing program. A total of 628 residents trained in the program over these 23 yr; they contributed a total of 1,721 resident years for analysis. Fewer faculty and certified nurse anesthetists were studied, so we do not include them in our analysis.

RESULTS

The incidence of substance use disorders among trainees in our department during the 10 yr before initiation of urine drug screening was four incidents in 719 resident years or 0.0056 incidents per resident-year. In the 13 yr after the introduction of urine drug screening, there have been zero incidents in 1,002 resident years in our residency program (P = 0.0305).

CONCLUSIONS

This single-center, comprehensive program including preplacement and random drug testing was associated with a reduction of the incidence of substance use disorders among our residents in anesthesiology. There were no instances of substance use disorders in our residents over the recent 13 yr. A large, multicenter trial of a more diverse sample of academic, government, and community institutions is needed to determine if such a program can predictably reduce the incidence of substance use disorders in a larger group of anesthesiology residents.

Drug use and fatal motor vehicle crashes: a case-control study

Drugged driving is a serious safety concern, but its role in motor vehicle crashes has not been adequately studied. Using a case-control design, the authors assessed the association between drug use and fatal crash risk. Cases (n=737) were drivers who were involved in fatal motor vehicle crashes in the continental United States during specific time periods in 2007, and controls (n=7719) were participants of the 2007 National Roadside Survey of Alcohol and Drug Use by Drivers. Overall, 31.9% of the cases and 13.7% of the controls tested positive for at least one non-alcohol drug. The estimated odds ratios of fatal crash involvement associated with specific drug categories were 1.83 [95% confidence interval (CI): 1.39, 2.39] for marijuana, 3.03 (95% CI: 2.00, 4.48) for narcotics, 3.57 (95% CI: 2.63, 4.76) for stimulants, and 4.83 (95% CI: 3.18, 7.21) for depressants. Drivers who tested positive for both alcohol and drugs were at substantially heightened risk relative to those using neither alcohol nor drugs (Odds Ratio=23.24; 95% CI: 17.79, 30.28). These results indicate that drug use is associated with a significantly increased risk of fatal crash involvement, particularly when used in combination with alcohol.

Drug violations and aviation accidents: findings from the US mandatory drug testing programs

AIMS

To assess the role of drug violations in aviation accidents.

DESIGN

Case-control analysis.

SETTING

Commercial aviation in the United States.

PARTICIPANTS

Aviation employees who were tested for drugs during 1995-2005 under the post-accident testing program (cases, n = 4977) or under the random testing program (controls, n = 1 129 922).

MEASUREMENTS

Point prevalence of drug violations, odds ratio of accident involvement and attributable risk in the population. A drug violation was defined as a confirmed positive test for marijuana (≥50 ng/ml), cocaine (≥300 ng/ml), amphetamines (≥1000 ng/ml), opiates (≥2000 ng/ml) or phencyclidine (≥25 ng/ml).

FINDINGS

The prevalence of drug violations was 0.64% [95% confidence interval (CI): 0.62-0.65%] in random drug tests and 1.82% (95% CI: 1.47-2.24%) in post-accident tests. The odds of accident involvement for employees who tested positive for drugs was almost three times the odds for those who tested negative (odds ratio 2.90, 95% CI: 2.35-3.57), with an estimated attributable risk of 1.2%. Marijuana accounted for 67.3% of the illicit drugs detected. The proportion of illicit drugs represented by amphetamines increased progressively during the study period, from 3.4% in 1995 to 10.3% in 2005 (P < 0.0001).

CONCLUSIONS

Use of illicit drugs by aviation employees is associated with a significantly increased risk of accident involvement. Due to the very low prevalence, drug violations contribute to only a small fraction of aviation accidents.